Hydraulic wedge



Sept. 28, 1954 c. B. EVENSON HYDRAULIC lWEDGE 3 Sheets-Sheet l Filed April 22, 1952 INVENTOR.

Sept. 2,8, 1954 c. B. EvENsoN HYDRAULIC WEDGE 5 Sheets-Sheet 2 Filed April 22, 1952 BNI NNN, um@ .hf NN mwN @d mwN ,nsw wu, nu. n. ,SW @n MMM mm Qu h uw E 1 W WWNWWMQS# vd. www i ma. i A l QN QQNMWI. r m MWNN NNN: rf hw. fo ff, n-\% QN y z `wN vNNmvmv NQ ATTD RN EYS ein mWAh/m Sept. 28, 1954 c. B. EvENsoN HYDRAULIC WEDGE 3 shets-sheet s Filed April 22, 1952 AQNWW .w w @Q a@ Patented Sept. 28, 1954 lTED STATES PATENT OFFICE 4 Claims.

This invention relates to a hydraulic wedge, and more particularly to a hydraulic wedge for use in felling heavy trees or other woodworking jobs.

rllhis invention is an improvement over the hydraulic wedge of my copending application, Serial No. 112,393, now Patent No. 2,657,904, granted November 3, 1953.

The object of the invention is to provide a hydraulic wedge which is adapted to be actuated by hydraulic iluid that is supplied by a pump that is operated by a saw chain, whereby the wedge can be positioned in a cutout in a tree to fell the tree or prevent binding or pinching of a saw that is being used.

Another object of the invention is to provide a hydraulic wedge which includes a pair of manually operable valves or cocks for regulating the movement of the wedge, there being ball bearings for insuring smooth movement of the parts.

A further object of the invention is to provide a hydraulic Wedge Which is extremely simple and inexpensive to manufacture.

Other objects and advantages will be apparent during the course of the following description.

In the accompanying drawings forming a part of this application, and in which like numerals are used to designate like parts throughout the same:

Figure 1 is a side elevational view, with parts broken away and in section, showing the wedge of the present invention with the dependent parts for operating the wedge;

Figure 2 is a top plan view of the hydraulic Wedge, constructed according to the present in- Vention;

Figure 3 is a longitudinal sectional view taken through the wedge of the present invention;

Figure 4 is a view similar to Figure 3, but with the jaws in their expanded position;

Figure 5 is a fragmentary sectional View illustrating the valve mechanism;

Figure 6 is a transverse vertical sectional View taken through the valve mechanism;

Figure 7 is a transverse sectional View taken through the wedge unit;

Figure 8 is a sectional vieW showing one of the elliptical bearings;

Figure 9 is a View similar to Figure 8, but show- .ing a modification wherein a ball bearing is used in lieu of the elliptical bearings;

Figure 10 is an enlarged, fragmentary, sectional view showing one of the end wedge guides;

Figure 1l is a vertical, longitudinal, sectional view of the hydraulic pump;

Figure 12 is a top plan view of the Wedge construction, With the ball bearings removed;

Figure 13 'is an enlarged elevational View of one of the spring assemblies;

Figure 14 is a plan view of the structure shown in Figure 13.

Referring in detail to the drawings, the numeral 3U designates the wedge unit of the present invention, Figure 1, while the numeral 3| designates a tank which is adapted to hold hydraulic fluid. A pump 32 is provided for pumping hydraulic uid from the tank 3l through a conduit 33, thence through a conduit 34, into the wedge unit 30, for actuating the latter. A return conduit 35 is provided for the passage of hydraulic uid from the wedge unit 35 back into the tank 3|.

The assembly is operated by means of a powerdriven chain saw 36, and the saw 36 includes a driven shaft 31 that has a cam 38 mounted thereon. The cam 38 is arranged in engagement with a roller 39, the roller 39 being rotatably connected to an arm 40. The other end of the arm 40 is pivotally connected by a pin 44 to a supporting body 45, and a pin 4| serves to pivotally connect the arm 40 to the upper end of a stem or rod 42 which forms part of the pump 32. The lower or inner end of the stem 42 is provided with a piston 43. The pump 32 includes a body 53 which is provided with a compartment or chamber 4B therein, Figure 11, and a bracket 41 extends from the bottom of the body 53 so that a suitable securing element 48 can be used for connecting the body 53 to a supporting structure 49, Figure 1. A pair of check valves 50 and 5l are arranged in the body 53, and the check valves serve to insure that hydraulic fluid will not be accidentally pumped in the wrong direction through the conduits 33 and 34. Thus, upon actuation of the saw 3B, the arm 4U Will be pivoted about the pin 4l, whereby the piston 43 will reciprocate in the body 53 to thereby cause hydraulic fluid to be pumped from the tank 3l to the wedge unit 30. A coil spring 54 is circumposed on the rod 42 for normally urging the rod 42 and piston 43 into their raised positions.

The wedge unit 3l) includes a housing 55, Figures 3 and 4, and formed integrally with the housing 55, or secured thereto is a rearwardly extending casing 56, the casing 56 being provided with a longitudinally extending bore 51, Figure l.

An opening 58 is arranged in the casing 5S, the ,opening 58 serving as a pop-off valve, so that air in the bore 51 can properly bleed therethrough. Slidably or reciprocably arranged in the bore 5l' is a plunger 59, and a stem or rod @il has one end connected to the plunger 59. The rod 6G slidably projects through an aperture cap @il which is arranged in threaded engagement with the end or" the casing 56, and mounted on the outer end of the rod Sil is a U-shaped bracket di which serves to rotatably support a pulley 52. The pulley i'f is rotatably connected to the bracket 6l by means of a pin B5, and a cable or cord 53 is trained over the pulley 62 for a purpose to be later described.

The housing 55 is provided with. a pair of opposed ports S and and a bushing are ranged in threaded engagement with the port t?, there being a similar bushing @Si arranged in threaded engagement with the other port d6. The conduit fill is connected to the bushing Eli, while the return conduit 35 is connected to the bushing S9. Rotatably supported in the housing 55 is a iirst valve le, the valve 'is being provided with a pair of curved passageways l?. A second valve i3 is also rotatably mounted in the housing 55, and the valve i3 is provided with a curved passageway A handle l is provided for manually rotating the Valve lil, while a smaller handle l is provided for rotating the other valve i3. A passageway l'i, Figure 3, exftends through a portion of the housing serves to at times connect the bore 5? to the valve iii. A small passageway 'i3 also serves t selectively connect the valve lil to an opening E9 which is arranged in a packing ring so that hydraulic fluid can at times pass through the passageway i8 and opening iii into the interior of a sleeve di for a purpose to be later described. A passageway 82 leads from the bushing 5S to the valve iii, and a similar passageway 33 leads from the other bushing @Q to the opposite side oi the valve le. A branch passageway 8e serves to connect the passageway @E to the second valve i3, and the valve i3 is adapted to be connected to the passageway S3 by means of L-shaped passageway 55. A spring Sii is provided for the valve le, while a similar spring Bi' is provided for the other valve lil, the springs 3o and serving to prevent accidental rotation of these valves.

The sleeve 8i is provided with left-hand threads 3S and right-hand threads 89, Figures 3 and 4. A cap @il is arranged in threaded engage nient with the right-hand threads 35i, and a packing ring si is interposed between the cap 9S and the end of the sleeve E Slidaoly or reciprocably arranged in the sleeve 8i is a piston 92, the front end of the piston 92 being shaped to denne wedge 93. A. head mi is secured to the rear end of the piston @2 by means of a screw 95, Figure 3. Thus, when hydraulic fluid is introduced. into the sleeve E, the piston s2 and wedge will be forced forwardly. t will be seen that the front end of the housing 5.5i is shaped to provide a chamber into which is threaded the sleeve El.

The wedge unit of the present invention further includes a plurality of 1cody members Se, each of which has one end pivotally connected to the housing by means of pins 9?. Pins d8 also serve to pivotally connect the body meinbers ed to a pair of pivotally mounted jaws 99. Each of the jaws E59 has a curved or arcuate shape, and the jaws Q9 are provided with a plurality of spaced teeth ilil, so as to facilitate the gripping of the jaws into the tree being felled.

The cable 63 is trained over a pair of guide pulleys it! which are rotatably connected to brackets m2 by means of a bolt-and-nut assembly or pin it, Figure l. The ends of the cable 63 are connected to ears ild which are ecured to the wedge 93. Thus, when the p, s2 and wedge 33 move orwardly from thD tion shown in Figure 3 to the position sho Figure 4, the plunger 59 will be moved loi in the bore l. Likewise, when the valv set so that the plunger 59 is moved rea;` in the bore E?, the cable 63 will cause the 92 and wedge 93 to move rearwardly in the wcdg unit.

The wedge S3 is provided with a plurality of spaced, parallel cutouts H15, Figures 7, 8 and l?, and arranged opposite to each of the cutouts in the wedge 93 is a similar cutout idd wl c arranged on the inner face oi the jaws cutouts HB5 and iil coact to provide ber races, and a plurality of elliptical bearings are arranged in the bearing races. These be ings il constantly rotate, and it will from Figure 7, and from Figures 3 and I there is suflicient space in these bearii enable the bearings itil to constanny whereby the jaws and wedge will move si relative to each other. If desired, i:y Tm ings 98 can be used in lieu of the elliptical oe ings lill, as shown in Figure 9, and the ball ings let are, of course, arranged si shaped bearing races.

A means is provided for guiding the wed during its sliding movement. This means prises a plurality of guide ribs idd which e n cured to the inner surfaces of the jaws iii-i lili. Each of the guide ribs i639 is provid an inclined edge i I l, Figure l0, and the edge i il slidably projects into a recess or i l2 in the wedge 93. Thus, 'the wedge C move back and forth, and the guide mehr o will insure that the wedge does not get out of alignment.

Spring means are provided for normally u ing the pair of jaws S9 toward each other. f spring means includes coil springs iid have their ends secured to exterior-ly t ed bushings H5, there being a nut lit arranco. on each of the bushings H5, Figures 7, i3 and le, By adjusting the nuts H6, the tension on the coil springs lid can be adjusted as desire In using the assembly of the present invention, a face cut is first made in the tree by vis of a suitable saw or other tool. During the sewing of the trees, the upper and lower parts of tree tend to bind on the saw, whereupon further movement of the saw is prevented. However, by means of the assembly of the present vention, the upper and lower parts of the tree can be maintained separated or spread 9 rt suiiiciently so that binding or pinching of the saw blade will be prevented. Thus, after the cut in the tree has been made, the we o S is positioned therein in the baci; cut cutting bark, so that the pair of jaws l the upper and lower parts of the tree. ure 4 the jaws 99 are shown in their es position, so that the upper and lower the tree will be maintained separated from or' other. To have the parts move from the pos tion shown in Figure 3 to the position shown in Figure 4, the Valve 'I3 is rotated by means of the handle i6, so that no hydraulic fluid will flow through the passageway '14, T'hen, the valve l5 is rotated or set by means of the handle so that hydraulic fluid will be pumped by the pump s2 from the tank 3|, through the conduit then through the conduit Sli, then through the passageway 82, and nally through the passageway '52, and thence through the opening 19 into the interior of the sleeve 8l, whereupon the piston 92 will be forced forwardly. As the piston 92 moves forwardly, the wedge 93 will cause the jaws 99 to move or pivot outwardly, as shown in Figure fi.

During this forward movement of the piston $2 and wedge 83, the cable 63 will cause the plunger '5e to move forwardly in the bore 5l, since the cable 63 is connected to the wedge 93. Any air which is in the bore il will either pass out through the pop-ofi opening 58 or through the passageway ll, then through the passageway 33, and out through the conduit 35. To retract the wedge 93, or cause the wedge 93 to move from the position shown in Figure 4 to the position shown in Figure 3, the valve 'i3 and valve 'id are adjusted as follows: The valve 'i3 is arranged so that no fluid .Hows therethrough, while the valve l@ is arranged so that the passageway 'il is connected to the short passageway 82 by means of the passageway 'H in the valve 1G. Then it wiil be seen that the other passageway 'i2 will connect the opening i9 with the passageway 223. Thus, hydraulic iiuid will pass through the passageway S2, then through the passageway 'li in the valve li), then through the passageway ll, to cause the piston 59 to move rearwardly in the bore 5l, whereby the cable 63 will retract the piston 92 and wedge 93. The hydraulic fluid that is arranged in the sleeve 8l will be forced up through the opening 'i9 and then through the passageway l2, and then through the passageway 83, and be returned to the tank 3| through the conduit 35. valve 'i3 and valve i0 are arranged as shown in Figure 3, so that no hydraulic fluid will flow therethrough.

The ball bearings of the wedge insure that there will be smooth movement between the various parts, and the springs IM tend to normally urge the pair of jaws together. The tension on the springs iid may be adjusted as desired. The wedge unit of the present invention is especially suitable for spreading a keri crack in wood, and the wedge unit is constructed so that the wood will not be unduly smashed, cracked or otherwise harmed during the felling of the tree.

What is claimed is:

l. In combination, a tank adapted to hold hydraulic iiuid, a wedge unit, a first conduit connecting said tank to said wedge unit, a pump for hydraulic iiuid from said tank through said conduit to said wedge unit, and a chainoperated cam for actuating said pump, said wedge unit comprising a housing provided with a pair of opposed ports, said rst conduit communicating with one of said ports and a second conduit connecting the other port to said tank, a casing projecting rearwardly from said housing and provided with a longitudinally extending bore, a plunger slidably arranged in said bore, a stem connected to said plunger, there being a chamber arranged in said housing, a hollow sleeve arranged in threaded engagement with said chamber, a rst manually operable valve rotatably arranged in said housing and provided with a pair of passageways for connecting said ports to said bore and to said sleeve, a second valve rotatably positioned in said housing for permitting the hydraulic fluid to by-pass the first valve, a plurality of body members pivotally connected to said housing, a pair of arcuate jaws pivotally connected to said body members and provided with a plurality of exterior teeth, a piston slid- To shut off the wedge unit, the

ably arranged in said sleeve, and a Wedge formed integrally with said piston for causing pivotal movement of said jaws, a pulley mounted on the free end of said stem, ears secured to said wedge, guide pulleys positioned exteriorly of said housing, and a cable trained over all of said pulleys and having its ends attached to said ears.

2. In a wedge unit, a housing provided with a pair of opposed ports, a casing projecting rearwardly from said housing and provided with a longitudinally extending bore, a plunger slidably arranged in said bore, a stem connected to said plunger, there being a chamber arranged in said housing, a hollow sleeve arranged in threaded engagement with said chamber, a first manually operable valve rotatably arranged in said housing and provided with a pair of passageways for connecting said ports to said bore and to said sleeve, a second valve rotatably positioned in said housing for permitting the hydraulic uid to by-pass the rst valve, a plurality of body members pivotally connected to said housing, a pair of arcuate jaws pivotally connected to said body members and provided with a plurality of exterior teeth, a piston slidably arranged in said sleeve, and a wedge formed integrally with said piston for causing pivotal movement of said jaws, bearing races arranged between said jaws and wedge, and spring members for normally urging said jaws toward each other, a pulley mounted on the free end of said stem, ears secured to said wedge, guide pulleys positioned eXteriorly of said housing, and a cable trained over all of said pulleys and having its ends attached to said ears.

3. In a wedge unit, a housing provided with a pair of opposed ports, a casing projecting rearwardly from said housing and provided with a longitudinally extending bore, there being an opening in said casing dening a pop oi valve, a plunger slidably arranged in said bore, a stem connected to said plunger, an apertured cap mounted on the rear end of said casing and slidably receiving said stem, there being a chamber arranged in said housing, a hollow sleeve arranged in threaded engagement with said chamber, a first manually operable valve rotatably arranged in said housing and provided with a pair or curved passageways for connecting said ports to said bore and to said sleeve, a second valve rotatably positioned in said housing and provided with a curved passageway for permitting hydraulic fluid to by-pass the first valve, there being a passageway extending through a portion of said housing and connecting said rst valve to said bore, there being a passageway connecting said rst valve to said sleeve, a plurality of body members pivotally connected to said housing, a pair of arcuate jaws pivotally connected to said body members and provided with a plurality of exterior teeth, a piston slidably arranged in said sleeve, a head secured to the rear end of said piston, and a wedge formed integrally with said piston for causing pivotal movement of said jaws, ears secured to said wedge, guide pulleys positioned extericrly of said housing, a cable trained over all of said pulleys and having its ends attached to said ears said wedge being provided with a plurality of spaced parallel cutouts, there being a, plurality of cutouts in the inner faces of said jaws arranged opposite to the cutouts in said wedge providing bearing races, a plurality of elliptical bearings rotatably arranged in said races, guide means for maintaining said wedge in alignment during its sliding movement, said guide means comprising a plurality of guide ribs secured to the inner surfaces of said jaws, each of said guide ribs being provided with an inclined edge, there being recesses in said wedge for receiving said inclined edges, and spring means for normally urging said pair of jaws towards each other, said spring means including bushings adjustably connected to said jaws, and coil springs having their ends secured to said bushings.

4. In a wedge unit, a housing provided with a pair of ports, a casing projecting rearwardly from said housing and provided with a bore, there being an opening in said casing defining a pop oi valve, a plunger slidably arranged in said bore, a stem connected to said plunger, an apertured cap mounted on said casing and slidably receiving said stem, a pulley mounted on said stem, there being a chamber arranged in said housing, a sleeve arranged in engagement with said chamber, a rst manually operable valve rotatably arranged in said housing and provided ith a pair of passageways for connecting said ports to said bore and to said sleeve, a second valve rotatably positioned in said housing and provided with a passageway for permitting hydraulic iluid to by-pass the rst valve, there being a passageway extending through a portion of said housing and connecting said rst valve to said bore, there being a passageway connecting said first valve to said sleeve, a plurality of body members pivotally connected to said housing, a pair of jaws pivotally connected to said body members and provided with a plurality of teeth, a piston slidably arranged in said sleeve,

8. a head secured to the rear end of said piston, a wedge formed integrally with said piston for causing pivotal movement of said jaws, ears secured to said wedge, guide pulleys positioned exteriorly of said housing, a cable trained over all of said pulleys and having its ends attached to said ears, said wedge being provided with a plurality of cutouts, there being a plurality of cutouts in said jaws providing bearing races, a plurality of bearings rotatably arranged in said races, guide means for maintaining said wedge in alignment during its sliding movement, said guide means comprising a plurality of guide ribs secured to said jaws, each of said guide ribs being provided with an inclined edge, there being recesses in said wedge for receiving said inclined edges, and spring means for normally urging said pair of jaws towards each other, said spring means including bushings adjustably connected to said jaws, and coil springs having their ends secured to said bushings.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 443,581 Marshall Dec. 30, 1390 1,395,209 Schultz Gct. 25, 1921 2,093,452 Joy Sept. 21, 1957 2,193,497 Spire Mar. lil, 1940 2,283,089 Pfauser May 12, 1942 2,385,753 Young Sept. 25, 1%5 2,497,836 Miller Feb. 14, 1950 2,505,847 Anuszkiewicz May 2, 1950 

